What is a magnet?

Magnet - is a piece of iron which will attract or repel pins, tacks, nails or anything else made of that metal. The word comes from a district in Thessaly, Greece, called Magnesia. It was here that men first noticed that certain black stones attracted iron. These stones were composed of an iron ore called magnetite and were natural magnets. Later it was discovered that if a piece of magnetite or lodestone leading stone was hung by a thread or floated on a piece of wood it would always turn to point north and south. This proved very useful to the early sailors. Next it was found that a magnet could be made by winding an insulated wire round a piece of iron and passing an electric current through the wire. This is called an electromagnetic and is used in an electric motor. Magnets can be made by stroking a piece of iron with lodestone or with another magnet thereby passing on the power of magnetism. In the middle of the 13th Ceentury a Frenchman, Petrus Perigrinus de Maricourt, carried out experiments in magnetism especially about its connection with the use of the compass as an instrument of navigation. In 1600 William Gilbert of Norwich who was Court Physician to Elizabeth I, published a book on magnetism called De Magneti.